# ast-query > Declarative JavaScript AST modification façade Latest version **2.0.0** (published 2016-06-10) · MIT license · 0 weekly downloads ## Install ```sh npm install ast-query pnpm add ast-query yarn add ast-query bun add ast-query ``` ## Health **Score 15/100 (F)** — status: abandoned. Positive: no vulnerabilities. Warnings: low downloads; no types; no esm support. Negative: abandoned; low maintenance score. ## Facts | | | |---|---| | Version | 2.0.0 | | Published | 2016-06-10 | | First published | 2013-07-29 | | Weekly downloads | 0 | | License | MIT | | TypeScript types | none | | Module format | CommonJS | | Dependencies | 5 | | Known vulnerabilities | 0 | | Install scripts | no | | GitHub stars | 249 | | Author | Simon Boudrias | | Maintainers | sboudrias | | Keywords | AST, source, traversal, syntax, tree | ## Links - npm: https://www.npmjs.com/package/ast-query - Repository: https://github.com/sboudrias/AST-query - Homepage: https://github.com/sboudrias/AST-query#readme - Issues: https://github.com/sboudrias/AST-query/issues - npm.io page: https://npm.io/package/ast-query ## Dependencies (5) - [lodash](https://npm.io/package/lodash.md) ^4.6.1 - [traverse](https://npm.io/package/traverse.md) ^0.6.6 - [acorn-jsx](https://npm.io/package/acorn-jsx.md) ^3.0.1 - [class-extend](https://npm.io/package/class-extend.md) ^0.1.1 - [escodegen-wallaby](https://npm.io/package/escodegen-wallaby.md) ^1.6.7 ## Alternatives - [update-check](https://npm.io/package/update-check.md) — 4.0M weekly downloads - [react-native-onesignal](https://npm.io/package/react-native-onesignal.md) — 134.5K weekly downloads - [react-redux-toastr](https://npm.io/package/react-redux-toastr.md) — 33.7K weekly downloads - [@nocobase/plugin-notification-manager](https://npm.io/package/@nocobase/plugin-notification-manager.md) — 2.0K weekly downloads - [react-simple-toasts](https://npm.io/package/react-simple-toasts.md) — 1.9K weekly downloads ## Recent versions - 2.0.0 (latest) — 2016-06-10 - 1.2.0 — 2016-03-15 - 1.1.1 — 2016-03-15 - 1.1.0 — 2015-12-23 - 1.0.1 — 2015-02-18 - 1.0.0 — 2015-02-18 - 0.3.1 — 2015-01-25 - 0.3.0 — 2014-09-19 - 0.2.5 — 2014-09-19 - 0.2.4 — 2014-05-07 - 0.2.3 — 2014-04-05 - 0.2.2 — 2014-04-05 - 0.2.1 — 2014-04-05 - 0.2.0 — 2014-04-05 - 0.1.0-pre.2 — 2014-02-28 - … 2 more at https://npm.io/package/ast-query/versions ## README AST Query ================ [![npm](https://badge.fury.io/js/ast-query.svg)](http://badge.fury.io/js/ast-query) [![tests](https://travis-ci.org/SBoudrias/AST-query.svg?branch=master)](http://travis-ci.org/SBoudrias/AST-query) [![dependencies](https://david-dm.org/SBoudrias/AST-query.svg?theme=shields.io)](https://david-dm.org/SBoudrias/AST-query) This project is a tentative to create a simple JavaScript AST modification library. If you've ever worked with AST trying to edit source code, you'll know it is a bad time. AST syntax is terse and forces you to loop a tree and use conditional structure a lot. AST Query hide these complexities behind a declarative façade. Making the simplicity choice means AST Query won't try to cover the full AST API. Rather we strive to answer commons needs. Getting Started ================ Install: `npm install --save ast-query` First, you need to pass a program code into AST query: ``` javascript var program = require("ast-query"); var tree = program("var a = 'foo'"); ``` This function returns a wrapped AST tree you can query and modify. Once you've modified the AST, get the source code back by calling the `toString` method on the tree. ``` javascript // ... tree.var("a").value("'bar'"); console.log( tree.toString() ); // LOG: var a = 'bar'; ``` Remember that you are editing source code. This mean you provide raw source code strings. This mean you need to double wrap strings (e.g.: `"'foo'"`). If that's not done, AST-query assume you're referencing a variable called `foo`. API ================ Program ---------------- ### `var tree = program( sourceCode, escodegenOptions, esprimaOptions )` - **sourceCode** (String) - The source code to edit. - **escodegenOptions** (Object) _optional_ - [escodegen](https://github.com/Constellation/escodegen) option object - **acornOptions** (Object) _optional_ - [acorn](https://github.com/ternjs/acorn) option object Returns an AST tree you can then query as explained below: ### `tree.var( name )` - **name** (String) - The variable name Find and returns a [`Variable` node](#variable-node). Given this code ``` js var bar = 23; ``` You'd call `tree.var('bar')` to get the Variable node. ### `tree.callExpression( name )` - **name** (String) - The name of the function or method being called. Find a function or method call and return a [`CallExpression` node](#callexpression-node) Given this code ```js grunt.initConfig({}); ``` You'd call `tree.callExpression('grunt.initConfig')` to get the CallExpression node. ### `tree.assignment( assignedTo )` - **assignedTo** (String) - The name (name or object) a value is assigned to Find and return an [`AssignmentExpression` node](#assignmentexpression-node). You'd call `tree.assignment('module.exports')` to query the code below: ```js module.exports = function () { // code }; ``` ### `tree.body` Property representing the program body in a [`Body` node](#body-node). ### `tree.verbatim( body )` - **body** (String) - The source code to inline verbatim Adds body and return a token assigment. ```js tree.body.append('var a = 1;' + tree.verbatim('ANYTHING')); ``` Variable node ----------------- ### `.value( value )` - **value** (String) _optionnal_ - A string containing the new variable value. It returns the current or new value wrapped in AST query interface. ### `.rename( name )` - **name** (String) - Change the variable name CallExpression node -------------------- ### `.filter( iterator )` - **iterator** (Function) - Function receiving each node as arguments and returning true to keep the current node in the returned set. Return a new CallExpression nodes collection with nodes passing the iterator test. ### `.arguments` A property pointing to an [`ArrayExpression` node](#arrayexpression-node) referencing the called function arguments. AssignmentExpression node -------------------- ### `.value( value )` Replace the assignment value with a new value or return the current value wrapped in an AST query interface. Literal node -------------------- A Literal node represent a raw JavaScript value as a String, a Number or a Boolean. ### `.value( value )` Get or update the value. FunctionExpression node ------------------- Node representing a function declaration (e.g. `function () {}`). ### `.body` Property pointing to a [`Body` node](#body-node) representing the function expression body. ObjectExpression node ------------------- ### `.key( name )` - **name** (String) - Key name Get a key value object or create a blank placeholder ### `value( value )` Replace current node with a new value. Returns the new value wrapped. ArrayExpression node ------------------- ### `.push( value )` - **value** (String) - value to push in the array ### `.unshift( value )` - **value** (String) - value to unshift in the array ### `.at( index )` - **index** (Number) - Index of the value to fetch Returns a value wrapped in an AST query interface. ### `value( value )` Replace current node with a new value. Returns the new value wrapped. Body node ------------------- ### `.prepend( code )` Preprend the given code lines in the body. If a `"use strict";` statement is present, it always stay first. ### `.append( code )` Append the given code lines in the body. Contributing ===================== **Style Guide**: Please base yourself on [Idiomatic.js](https://github.com/rwldrn/idiomatic.js) style guide with two space indent **Unit test**: Unit test are wrote in Mocha. Please add a unit test for every new feature or bug fix. `npm test` to run the test suite. **Documentation**: Add documentation for every API change. Feel free to send corrections or better docs! **Pull Requests**: Send _fixes_ PR on the `master` branch. Any new features should be send on the `wip`branch. License ===================== Copyright (c) 2013 Simon Boudrias (twitter: @vaxilart) Licensed under the MIT license. --- _Source: https://npm.io/package/ast-query · Machine-readable twin of the npm.io package page. Health data is recomputed on every publish._